A conventional information processing apparatus, such as a word processor and a computer, often employs keyboard entry. In such an information processing apparatus, when editing a document, for example, a character or a block of text to be edited is specified by moving a cursor using the keyboard, and a desired editing operation is executed using edit keys.
In recent years, an apparatus, which enables data entry by directly pointing a screen provided with a tablet by means of a pen for inputting coordinates, has been developed. There is an apparatus of this type having a gesture function to edit a document by handwriting. With this apparatus, when a line as an edit symbol is drawn on the screen with a pen, an editing operation specified by a command corresponding to the pattern of the line is performed. Such an information processing apparatus generally does not use a cursor, or switches between cursor movements and gesture entry using a pen provided with a switch.
However, with conventional word processors, generally, cursors are used when executing operations. Therefore, if there is no cursor, i.e., pointing means, a drawback occurs in terms of handling. Moreover, it is not desirable to provide a switch on the pen as it causes an increase in the cost and requires troublesome switching operations.
Moreover, a conventional editing operation using a gesture has the following drawbacks.
First drawback is that a great deal of effort is required to learn editing techniques. More specifically, a method of specifying characters to be edited varies depending on commands. Therefore, the user needs to learn the pattern of a line representing each command and a specifying method corresponding to each command. In the case of a command to delete one character by drawing a mountain-like line, for example, if the peak of the mountain shape is arranged to be a reference location for editing, the mountain peak of the line is needed to drawn over the character to be edited.
The second drawback is an inefficient editing process. In conventional gesture entry, putting down a pen on a screen to draw a line and lifting up the pen from the screen after drawing are treated as a single process. Consequently, the effectiveness of an input by pen is determined after the pen is lifted up, resulting in longer processing time.
In this case, if the input pen is moved into an area where gesture entry is unavailable, the gesture processing stops and an error message is given. Therefore, care needs to be taken throughout the input operation, i.e., from the start of drawing to the end of drawing, requiring rather complicated handling.
In order to effectively use the conventional gesture entry function, the trace of the input pen and a list of edit commands are displayed. However, the processing time is increased because the display of the trace of the input pen and the list of commands is caused to appear and disappear repeatedly.
The third drawback is that edit processing becomes ineffective in the area of the screen where editing by gesture entry is unavailable. For example, when the input pen is moved into the area, particularly into an input area having icons, the input made in the input area is taken first and therefore the input made to execute the gesture entry is cancelled. In this case, drawing must be started again by insuring that the input pen does not pass through the area.
The fourth drawback is that mistaken handling likely causes editing errors. For example, if an edit symbol for deletion is mistakenly entered, a character or text is unnecessarily deleted. Extra time is required to restore the mistakenly deleted character or text.